Air-insulated medium-voltage circuit-breaker modules for installation outdoors are commonly made up of circuit-breaker boxes for installation indoors that are placed inside a protective metal enclosure and which are connected to electricity lines via air/air type current feedthroughs mounted in openings in a roof-forming wall of the enclosure. Such outdoor circuit-breaker modules are generally associated with disconnectors that are situated outside the enclosures and which enable the boxes to be isolated to allow access to the components thereof for maintenance or replacement purposes, or indeed to isolate the incoming and outgoing feeders connected thereto. Such combinations of equipment are relatively large and complex.
Document FR-A-2 683 940 describes an embodiment of a medium-voltage circuit-breaker for outdoor installation which also constitutes its own disconnector. Disconnection is implemented by tilting its poles between a position in which the poles are electrically connected to connection feedthroughs of the circuit-breaker, and a position that is situated angularly at 90.degree. therefrom and in which the poles are isolated from the feedthroughs. That circuit-breaker is incorporated in a module having a circuit-breaker support drawer suitable for being extracted in part in order to enable operating personnel to take action thereon for maintenance and/or replacement purposes. More specifically, provision is made to connect the circuit-breaker and disconnector unit to live bare conductors which extend laterally as far as the circuit-breaker. This implies that the module must be installed high up, on a pylon, to comply with safety standards. Such a solution presents serious drawbacks in terms of controlling the circuit-breaker and of giving operating personnel access to the various components situated inside the module that includes the circuit-breaker.